ROI of power conditioning is determined by utilization

Power conditioning is one aspect of an enterprise that has always been low profile but extremely vital to the existence of organizations. A brief discussion with Peter A Panfil, Vice President, Power Engineering, Liebert Corporation about the trends and factors to look out for in Enterprise Power Conditioning. by Anil Patrick R

What are the latest trends in power conditioning?

The most recent trend in the power conditioning area is that organizations don't want their systems to ever go down. There might be people who say that this is not a recent trend, since organizations always had this requirement and capability. This is where the difference between yesterday's power conditioning systems and today's systems lies. Differences lie in the maintenance cycles of the systems of past and present. Today's power systems require zero maintenance.

One of the best areas to demonstrate these differences is in data centers. The power systems in data centers do not have maintenance cycles any more. It's zero maintenance or 'hot maintenance' now, where we have a system that is always running. This gives enterprises the capability to do maintenance without taking down the system when required. This is done using systems like the dual bus architecture.

Today, organizations place higher expectations on vendors to ensure they have the highest availability. For example, users these days are looking to ensure that their UPS is coordinated to the operation of their static switch when running their dual bus architectures. They are making sure that they have complete coordination there. Factors like having their power distribution network in coordination with their UPS system is sorted out. Fault management and mitigation is also handled to ensure highest availability.

What are the basic redundancy features that an enterprise should look for when going in for power conditioning solutions?

First of all comes the highest availability with redundant features. For example, systems like a dual bus redundant system. In that case, we've got two UPS buses in parallel. Static switches are used to switch between these buses in case of bus failures.

Next comes MTBF (Mean Time Between Failure). It is necessary to go in for systems with high MTBF. This way, it is possible to get extremely reliable products with backup source. Consider the case of having another UPS with similar MTBF in parallel. The occurrence factor of both of them going down at the same time and having a static switch fail, as well, is extremely low in its probability.

Local and global redundancy capabilities are also very important. Within the unit itself, there should be critical redundancy circuits for local bypass as well as for power supply, cooling fans, etc. The UPS needs to have redundancy for the components inside it too. In most cases, UPSs are made with respect to redundancy vs cost.

Are there any ideal ways of managing an enterprise power infrastructure?

The general framework is to have components like a utility feed, a backup generator, and isolated battery points. The ideal way to manage this is to have separate utility feeds. Now, this is very difficult to execute, even for setups that are close to concentrated utility grids. It is difficult to pull one utility from one grid line and the second from another grid line.

It is due to this that there is a central utility grid, redundant generators, dual bus (bus A and bus B), and static switch architecture to switch between buses. We think that this is the most reliable and gives highest availability. It's not always easy to manage this architecture, though. Ideally, grounding in this case has to be done as close to the load as possible. This simplifies fault management and also the returns of faults happening through that grounding mechanism. Neutral management is also very important.

What do you think are the common mistakes that enterprises make on the power conditioning front?

The biggest thing that today's enterprise neglects is battery maintenance. As vendors we observe and analyze every critical bus failure that our customers face. You will be surprised at how many of those critical bus failures are either the direct or indirect results of not having properly maintained batteries. So battery maintenance is very important.

The other thing is that, from a design standpoint, well-executed fault coordination and fault coordination studies are important. A good example I can give is that we might do a fault coordination study of an entire system and it works exactly as the system is expected to work. And then, somehow, the upstream breaker at the input to my building doesn't have the same coordination factors that the power system in my facility has. So I might have a particular set of peak currents that I have to deal with. The UPS system will handle this just fine, but the upstream system cannot handle it.

Some of these problems occur because the enterprise is growing. As it grows, more and more UPSs are added to the setup. What is usually neglected in such a scenario is that no effort is spared to go back and ensure that what input comes into the system or is distributed to the UPSs, have the same kind of capabilities. Good fault coordination and management is very important, considering such issues.

The third thing is to have an effective mechanism to manage change in system configurations. This makes sure that if there are separate pieces of equipment, they run fully as a single system. For us, it is configuration from a maintenance standpoint.

And then, I would say that the next important issue is grounding and neutral management. You have to check in detail at the time of commissioning if the ground is proper, the neutrals are done properly, that there is adequate source feed, and that there is an adequate load feed as well.

How can ROI be calculated for power conditioning?

It is really the customer's utilization of the setup that matters when it comes to ROI. This is why ROI is highest for a data center. Next in line comes the refineries. Refineries have maintenance schedules no less than two years. Once they've got the setup started, they don't have a chance to touch the infrastructure. If some equipment does not function, it will produce wrong data or wrong material leading to immense losses. In such cases, attaching a figure to ROI is not possible.

Financial institutions dealing with global trades running 24 hours, are customers that can never afford to go down. I have figures from thousands of dollars per minute to multiples of thousands of dollars per minute as losses if the system goes down.

Our position is that it is very simple to justify a redundant system. All you need to do is to look at the expenses incurred by a startup and shutdown situation as well as the loss of revenue from trading. The issue is that it depends on the company itself. The organization has to decide by balancing against the system cost and decide what can be tolerated.

Anil Patrick R can be reached at: anilpatrick@networkmagazineindia.com